Prior to the development of the modern chemical and pharmaceutical industries essential oils were used in many areas of daily life as antiseptic and disinfectant materials in pharmaceutical and cosmetic applications such as antimicrobial and larvicidal agents. Essential oil based formulations with a broad spectrum of antimicrobial activity have been shown to be relatively nontoxic to mammals. They have been replaced with more potent synthetic chemicals and antibiotics, which are cheaper and highly effective and can be used in lower concentrations. With time, however, the toxicity and environmental effects of these synthetic chemicals have been revealed, and there is now an effort to replace them with the same essential oil agents that they had originally replaced.
The use of such essential oil based formulations in agriculture has also been reported. PCT Publication No. WO 04/098767 (Application No. PCT/IL2004/000394), to the inventors of the present application, disclose microcapsules of essential oils which may be used as disinfectant products for the consumer market as hard-surface cleaners, laundry detergents and softeners, as pesticides, insect repellents, and as antiviral or antifungal agents. When the microcapsules are applied to given substrates, the essential oil contained therein is released at a constant rate over a period of time. The efficacy of such microcapsules depends solely on parameters relating to the microcapsules themselves, i.e., size, thickness of the encapsulating membrane, ability to sustain release of the essential oil contained therein, etc., and not on the aqueous medium which carries them to the target environment and which dries immediately thereafter.